I did some checking and the app requests about 130kb when it requests the registration list, and when it requests a check in record 2kb.
So 25 GB seems like it’d be enough if it’s only going to be used by the apps to connect to your site.

With regards to the server, we recommend upgrading to PHP 7 if that’s possible. The PHP version may or may not be available as a setting within your web hosting account.

Also, it may help to upgrade the server to a plan where more resources are available (depending on what’s currently available from your web host).

For example, Digital Ocean has a number of tiers available for their droplets:https://www.digitalocean.com/pricing/
If the current plan had a 2GB memory limit, an upgrade to a 4GB plan would be a nice upgrade. It’d also be an upgrade to go from a Standard Droplet to an Optimized Droplet.

Thanks Josh for the reply about the amount of data downloaded. I think we’ll have enough with 25GB.

The website is with WPEngine. They say, when I asked them, that “on a shared server, memory is allocated through the server, your one site isn’t allocated a specific memory limit. Your site is provided the amount of memory it needs to be able to run efficiently.” Which seems to be a nice diplomatic answer, but doesn’t actually tell us much.

Should I increase the current settings in wp_config to match these? This seems to be a different magnitude of order from the 4GB you were talking about on the digital ocean pricing page. Must be a different thing …

The website is with WPEngine. They say, when I asked them, that “on a shared server, memory is allocated through the server, your one site isn’t allocated a specific memory limit. Your site is provided the amount of memory it needs to be able to run efficiently.” Which seems to be a nice diplomatic answer, but doesn’t actually tell us much.

On a shared server you have one server with multiple sites, each of those sites all share the resources available on that server so when you set the site to have 512MB of memory, you’re basically saying allow this site to go up to 512MB of available memory. If it’s not available as another site is already using some of it, you don’t get it.

Similar situation with the database, each site makes connections to MySQL which has to handle those connections, retrieve the data and send it back and so. The more connections or more data being pulled the longer your wait for your ‘turn’.

Shared servers are fine for low traffic/low resource sites but not great for ecommerce.

Should I increase the current settings in wp_config to match these?

You can, but that doesn’t mean you’ll actually get 512MB of RAM because its available ram, shared between all sites.

This seems to be a different magnitude of order from the 4GB you were talking about on the digital ocean pricing page. Must be a different thing

It is a different thing, Digital Ocean ‘droplets’ are VPS.

A VSP is still a shared server but done in a very different way, your shared instance on the server has its own allocation of RAM specifically for it.

So you may have a site with 32GB of RAM and then you can have 8 VPS’s on that server (8 x 4GB is 32GB). Your VPS always has those 4GB’s available to it and doesn’t share that with others…. the trade off with Digital Oceon is YOU now manage your own server.

If that’s not something you are prepared for you can find managed VPS packages that may be better (though they are much more expensive than DO or shared hosting).